Numerous exploratory programs in propulsion have resulted in the development of high-performance smokeless propellants; however, the development of inert components which do not contribute to smoke in the exhaust after the propellant has been consumed has been overlooked to a large extent. The inert components can be identified as mainly the liner, insulation, and other thermal barriers. The liner is the intermediate chemical film or strata which bonds the motor wall or wall insulation to the propellant grain. In the past, the liner materials and the insulation materials have produced amounts of smoke from pyrolysis and ablation after burnout of the propellant which can sometimes exceed that produced by the propellant itself.
It is apparent that the advantages of a high-performance smokeless propellant would be offset by a major afterburning condition which produced smoke of a substantial amount.
Therefore, an object of this invention is to provide a chemical additive which is effective in functioning to prevent smoldering of the liner, and by thus preventing smoldering of the liner; the pyrolysis and ablation of the insulation material would not be a problem.
Another object of this invention is to provide a liner composition with an afterburning retardant for use with composite propellant grains.
A further object of this invention is to provide a liner composition with an afterburning retardant for use with double-base propellant grains.